z

µ

s

standard error

30

The distribution of sample means is almost perfectly normal if (1) the population from the which the samples are selected is a normal distribution and (2) the number of scores in each sample is relatively large, around ___ or more.

Type I

Type II

power, power

The ___ of a statistical test is the probability that the test will correctly reject a false null hypothesis. That is, ___ is the probability that the test will identify a treatment effect if one really exists.